The Biosensor/Interaction Analysis Core was formally established in 1997 to meet the growing need for macromolecular interaction analysis. Initial funding was partially provided by the Cancer Center, through both Core Grant Developmental Funds and non-Core Grant sources, as well as by the School of Medicine. Irwin Chaiken, PhD, Professor of Medicine, serves as Facility Director. Dr. Chaiken is a national expert in kinetic interaction analysis using biosensors as well as in the field of biomolecular recognition. Dr. Chaiken's laboratory was one of the first to apply the use of biosensory technology to specific macromolecular interaction systems. This biosensor work emerged from Dr. Chaiken's earlier work in the development of analytical affinity chromatography for interaction analysis using immobilized ligands. Dr, Chaiken planned and established the Biosensor/Interaction Analysis ore and now serves as it's Facility Director. The facility's Technical Director,. Gabriela Canziani, PhD, has more than ten years of experience in enzyme kinetics, structure-function of the catalytic sites of enzymes, and spectrophotometric methods, including fluorescence spectroscopy and biophysical analysis of lipid- protein interactions. Usage has increased steadily during this start-up period. The vast majority of users are repeat customers who are increasing their usage by both expanding the scope of current projects and initiating new projects. During the most recent budget year, 83% of usage was done by Cancer Center members and 79% was by Cancer Center members with peer- reviewed funding. Increased usage by Cancer Center members is very much anticipated for the next project period as this core becomes an NCI- approved Cancer Center Shared Resources and as more investigators become familiar with its growing capabilities.